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From: "K. Macy" <kmacy@freebsd.org>
To: Luigi Rizzo <rizzo@iet.unipi.it>
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Subject: Re: FreeBSD I/OAT (QuickData now?) driver
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> This said, one should consider that going fast and being
> completely general don't go well together -- you don't do
> F1 races with a minivan, and don't carry large groups of
> people around with an F1 car.

This is self-evident, any sort of multiplexing comes at a price. To
have the card be simultaneously general and support direct access
requires dedicated hardware like the quasi-IOMMU on the Solarflare
cards.

> I don't think we'll ever manage
> to have both at the same time. It is good to have a
> "transformer" vehicle though!

>From my point of view, the general utility of this all boils down to
how easy it is to use the "bridge". I'll take a look in to interfacing
to netmap with my user level TCP stack to get a feel for the latter.

Thanks for the clarification.

-Kip